At present, the most commonly used materials for the packaging of open cell panels are foam cushioning materials, such as Expandable Polyethylene (EPE) and expanded polypropylene (EPP). The packaging method is basically a sealed way, that is, each box is closely stacked, wrapped around the stack with a wrap film, and covered with a polyethylene (PE) waterproof membrane on the top of the stack. However, it is not uncommon to find that mist or water droplets sometimes form inside the wrap film or even the box after a product is shipped to a destination for unpacking.
There are two reasons for this phenomenon: first, the water vapor in high humidity environment through the outer protective film and the top cover film into the package; second, the temperature difference between different environments lead to the condensation of water vapor into water droplets and stored in the box body. After a variety of ways to try and found that the temperature difference between inside and outside the box is the main reason for the box body into the water. In response to this phenomenon, the common practice is to place a desiccant inside the box to absorb moisture, but the effect is not ideal. And the location of the desiccant is fixed; the desiccant cannot completely absorb the moisture in all parts of the box.